The research efforts at the McArdle Laboratory for Cancer Research are directed toward an understanding of the mechanisms of viral and chemical carcinogenesis, the critical features of neoplastic cells, and the characterization of biological and biochemical functions which are directly or indirectly related to the neoplastic transformation. The carcinogenesis is studied include detailed examinations of the transformation of cells by the RNA tumor viruses, the immunogenetics of the murine leukemia virus, the analysis of the induction of malignancy in the whole animal and in culture, the activation of chemical carcinogens, and the characterization of the biochemical processes accompanying malignant transformation. Studies are in progress on the regulation of DNA synthesis and of genetic transcription in eukaryotic and prokaryotic cells. A number of these studies utilize the slime mold, Physarum polycephalum, because of its highly synchronous mitotic divisions. The regulation of genetic expression in normal and neoplastic mammalian liver cells, both at the transcriptional and translational cells, is also under study. Detailed investigations are underway on the structure and function of the nuclear envelope and of the endoplasmic reticulum in normal and neoplastic cells.